We're dividing 619621 by 31 
The aim is to understand the frequency of 31 in 619621.

Going ahead to step 1:
31 goes into 6 0 times with a remainder of 6.
Use 0 as the next digit of our solution. 
Result so far: 0.0
If we take 0 away from 6, we end up with 6.
Include the next digit (1) from the dividend after 6, then repeat: 61 / 31

Moving on to step 2:
61 divided by 31 is 1 with a remainder of 30.
The number 1 becomes the next digit in our result. 
Result so far: 1.0
The remainder is 30 after subtracting 31 from 61.
Bring next digit (9) of the dividend behind the 30 and repeat the process: 309 / 31

Moving on to step 3:
31 goes into 309 9 times with a remainder of 30.
Put 9 as the next digit of the answer. 
Result so far: 19.0
Subtracting 279 from 309 leaves us with 30.
Include the next digit (6) from the dividend after 30, then repeat: 306 / 31

Advancing to step 4:
The number 31 fits into 306 9 times, leaving a remainder of 27.
Use 9 as the next digit of our solution. 
Result so far: 199.0
The remainder is 27 after subtracting 279 from 306.
Take the next digit (2) from the dividend and append it to 27, then repeat: 272 / 31

Advancing to step 5:
When dividing 272 by 31, we get 8 with a remainder of 24.
The number 8 becomes the next digit in our result. 
Result so far: 1998.0
Subtract 248 from 272 to get 24.
Fetch the next digit (1) from the dividend, attach it to 24 and continue: 241 / 31

Going ahead to step 6:
31 goes into 241 7 times with a remainder of 24.
Put 7 as the next digit of the answer. 
Result so far: 19987.0
Subtract 217 from 241 to get 24.
Since there are no more digits in the dividend, we add a zero to the remainder making it 240, and continue the process.

Going ahead to step 7:
31 can be fit into 240 7 times, resulting in a remainder of 23.
Record the quotient 7 as the next digit in the result. 
Result so far: 19987.7
Deduct 217 from 240 and we're left with 23.
Since there are no more digits in the dividend, we add a zero to the remainder making it 230, and continue the process.

Step 8:
230 divided by 31 is 7 with a remainder of 13.
The next digit of our result is 7. 
Result so far: 19987.77
Deduct 217 from 230 and we're left with 13.
Since there are no more digits in the dividend, we add a zero to the remainder making it 130, and continue the process.

The final result is 19987.77 with a remainder of 0.013.